Jeganathan Manivannan

Sinapic Acid Prevents Hypertension and Cardiovascular Remodeling in Pharmacological Model of Nitric Oxide Inhibited Rats

Objectives Hypertensive heart disease is a constellation of abnormalities that includes cardiac fibrosis in response to elevated blood pressure, systolic and diastolic dysfunction. The present study was undertaken to examine the effect of sinapic acid on high blood pressure and cardiovascular remodeling. Methods An experimental hypertensive animal model was induced by L-NAME intake on rats. Sinapic acid (SA) was orally administered at a dose of 10, 20 and 40 mg/kg body weight (b.w.). Blood pressure was measured by tail cuff plethysmography system. Cardiac and vascular function was evaluated by Langendorff isolated heart system and organ bath studies, respectively. Fibrotic remodeling of heart and aorta was assessed by histopathologic analyses. Oxidative stress was measured by biochemical assays. mRNA and protein expressions were assessed by RT-qPCR and western blot, respectively. In order to confirm the protective role of SA on endothelial cells through its antioxidant property, we have utilized the in vitro model of H2O2-induced oxidative stress in EA.hy926 endothelial cells. Results Rats with hypertension showed elevated blood pressure, declined myocardial performance associated with myocardial hypertrophy and fibrosis, diminished vascular response, nitric oxide (NO) metabolites level, elevated markers of oxidative stress (TBARS, LOOH), ACE activity, depleted antioxidant system (SOD, CAT, GPx, reduced GSH), aberrant expression of TGF-β, β-MHC, eNOS mRNAs and eNOS protein. Remarkably, SA attenuated high blood pressure, myocardial, vascular dysfunction, cardiac fibrosis, oxidative stress and ACE activity. Level of NO metabolites, antioxidant system, and altered gene expression were also repaired by SA treatment. Results of in vitro study showed that, SA protects endothelial cells from oxidative stress and enhance the production of NO in a concentration dependent manner. Conclusions Taken together, these results suggest that SA may have beneficial role in the treatment of hypertensive heart disease by attenuating fibrosis and oxidative stress through its antioxidant potential.

Sinapic acid protects heart against ischemia/reperfusion injury and H9c2 cardiomyoblast cells against oxidative stress

The present study was designed to evaluate antioxidant and cardioprotective potential of sinapic acid (SA) against ischemia/reperfusion (I/R) injury. Cardiac functional recovery after I/R was evaluated by percentage rate pressure product (%RPP) and percentage coronary flow (%CF). Myocardial injury was evaluated by 2,3,5-triphenyltetrazolium chloride (TTC) staining and LDH enzyme leakage. Oxidative stress was estimated by lipid peroxidation level. eNOS protein expression in reperfused heart was assessed using Western blot method. Finally, in order to support the antioxidant effect of SA, in vitro protective potential of SA was assessed on H2O2-induced oxidative stress in H9c2 cardiomyoblast cells. The overall results demonstrated that I/R induced cardiac dysfunction, injury and oxidative stress was attenuated by SA treatment. Moreover, in vitro results also shown that, SA protects H9c2 cells from oxidative stress and modulates mitochondrial membrane permeability transition (MPT). In conclusion, coupled results from both in vivo and in vitro experiments have confirmed that SA with antioxidant role protects cardiac cells and its functions from I/R induced oxidative stress.

Prevention of cardiac dysfunction, kidney fibrosis and lipid metabolic alterations in l-NAME hypertensive rats by sinapic acid--Role of HMG-CoA reductase.

The present study was designed to evaluate the effect of sinapic acid, a bioactive phenolic acid on high blood pressure associated cardiac dysfunction, kidney fibrosis and lipid alterations in N(ω)-nitro-l-arginine methyl ester hydrochloride (l-NAME) induced hypertensive rats. Sinapic acid was administered to rats orally at a dosage of 40 mg/kg everyday for a period of 4 weeks. Sinapic acid treatment significantly decreased mean arterial pressure, left ventricular end diastolic pressure, organ weights (liver and kidney), lipid peroxidation products in tissues (liver and kidney), activities of hepatic marker enzymes and the levels of renal function markers in serum of l-NAME rats. Sinapic acid treatment also significantly increased the level of plasma nitric oxide metabolites, and enzymatic and non-enzymatic antioxidants in tissues of l-NAME rats. Tissue damage was assessed by histopathological examination. Alterations in plasma angiotensin-converting enzyme activity, level of plasma lipoproteins and tissue lipids were corrected by sinapic acid treatment in l-NAME rats. Sinapic acid treatment significantly decreased the activity of 3-hydroxy-3-methylglutaryl-Coenzyme A (HMG-CoA) reductase in plasma and liver, whereas the activity of lecithin cholesterol acyl transferase was significantly increased in the plasma of hypertensive rats. Docking result showed the interaction between sinapic acid and HMG-CoA reductase. Sinapic acid has shown best ligand binding energy of -5.5 kcal/M. Moreover, in chick embryo model, sinapic acid improved vessel density on chorioallantoic membrane. These results of the present study concludes that sinapic acid acts as a protective agent against hypertension associated cardiac dysfunction, kidney fibrosis and lipid alterations.

Disturbed flow mediated modulation of shear forces on endothelial plane: A proposed model for studying endothelium around atherosclerotic plaques

Disturbed fluid flow or modulated shear stress is associated with vascular conditions such as atherosclerosis, thrombosis, and aneurysm. In vitro simulation of the fluid flow around the plaque micro-environment remains a challenging approach. Currently available models have limitations such as complications in protocols, high cost, incompetence of co-culture and not being suitable for massive expression studies. Hence, the present study aimed to develop a simple, versatile model based on Computational Fluid Dynamics (CFD) simulation. Current observations of CFD have shown the regions of modulated shear stress by the disturbed fluid flow. To execute and validate the model in real sense, cell morphology, cytoskeletal arrangement, cell death, reactive oxygen species (ROS) profile, nitric oxide production and disturbed flow markers under the above condition were assessed. Endothelium at disturbed flow region which had been exposed to low shear stress and swirling flow pattern showed morphological and expression similarities with the pathological disturbed flow environment reported previously. Altogether, the proposed model can serve as a platform to simulate the real time micro-environment of disturbed flow associated with eccentric plaque shapes and the possibilities of studying its downstream events.

Diosgenin, a steroidal saponin, prevents hypertension, cardiac remodeling and oxidative stress in adenine induced chronic renal failure rats

Patients with chronic renal failure (CRF) are at a high risk of developing cardiovascular diseases. The aim of the present study was to evaluate the effect of diosgenin on blood pressure, cardiac remodeling, contractile function and gene expression program in the context of oxidative stress in CRF rats. CRF was induced in rats by feeding them with 0.75% adenine-containing diet, and diosgenin was given orally everyday at the dose of 10, 20 and 40 mg kg−1 body weight of animal. The effect of diosgenin on systolic blood pressure (SBP), activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), angiotensin converting enzyme (ACE) activity and lipid peroxidation level in heart were evaluated. Cardiac function (dp/dt) and percentage rate pressure product (%RPP) recovery after ischemia/reperfusion (I/R) were evaluated by Langendorff isolated heart system, and gene expression levels were assessed by real-time PCR. Fibrotic remodeling of heart was assessed by histopathologic analyses. The outcome of this study demonstrated that a dose dependent treatment with diosgenin reduces hypertension in CRF animals, and a 40 mg kg−1 dosage exhibited more pronounced effect on the blood pressure. Diosgenin enhances the antioxidant level, attenuates ACE activity, lipid peroxidation level and cardiac fibrosis. Ventricular function and %RPP recovery after I/R were also improved by the diosgenin treatment. CRF induced expression of transforming growth factor-β (TGF-β) and β-myosin heavy chain (β-MHC) were also suppressed by diosgenin. Taken together, these results suggest that diosgenin have enough potential to attenuate cardiac remodeling by reducing blood pressure and oxidative stress in the heart of CRF rats.

Systems pharmacology and molecular docking strategies prioritize natural molecules as cardioprotective agents

Natural compounds can interact with multiple cellular target proteins and may be prioritized as drug leads. There is a need for prioritization of compounds that protect cardiovascular systems from pathological conditions. Here we prioritize morin, veratric acid, piperine, syringic acid, vanillic acid, diosgenin, diosmetin and sinapic acid that were already identified as cardioprotective molecules in our previous studies through multi-level data integration. In this study, initially we predict targets of the above-mentioned compounds by reverse pharmacophore (PharmMapper) and structural similarity based target-screening methods. We also explored the compound–target pathways (Biocarta and KEGG) and disease relationships. Further, we chose public microarray transcriptomic data from GEO to prioritize important pathogenic targets (heart failure, cardiac hypertrophy, vascular dysfunction and atherosclerosis), and we explored the interaction potential of the above compounds on the targets via blind docking (AutoDock Vina). Moreover, the multi target action of compounds was revealed by target information retrieved from large-scale text mining and organized databases (HIT and TCMID). The drug likeness profile and toxicity prediction was achieved based on Lipinskis rule and structural similarity search (ProTox). The observed results have demonstrated that the multi target potential and less toxic nature mean these molecules can be prioritized as lead compounds for cardiovascular diseases.

Transcriptomic analysis of thalidomide challenged chick embryo suggests possible link between impaired vasculogenesis and defective organogenesis

Since the conception of thalidomide as a teratogen, approximately 30 hypotheses have been put forward to explain the developmental toxicity of the molecule. However, no systems biology approach has been taken to understand the phenomena yet. The proposed work was aimed to explore the mechanism of thalidomide toxicity in developing chick embryo in the context of transcriptomics by using genome wide RNA sequencing data. In this study, we challenged the developing embryo at the stage of blood island formations (HH8), which is the most vulnerable stage for thalidomide-induced deformities. We observed that thalidomide affected the early vasculogenesis through interfering with the blood island formation extending the effect to organogenesis. The transcriptome analyses of the embryos collected on sixth day of incubation showed that liver, eye, and blood tissue associated genes were down regulated due to thalidomide treatment. The conserved gene coexpression module also indicated that the genes involved in lens development were heavily affected. Further, the Gene Ontology analysis explored that the pathways of eye development, retinol metabolism, and cartilage development were dampened, consistent with the observed deformities of various organs. The study concludes that thalidomide exerts its toxic teratogenic effects through interfering with early extra-embryonic vasculogenesis and ultimately gives an erroneous transcriptomic pattern to organogenesis.

A proteome-wide systems toxicological approach deciphers the interaction network of chemotherapeutic drugs in the cardiovascular milieu

Onco-cardiology is critical for the management of cancer therapeutics since many of the anti-cancer agents are associated with cardiotoxicity. Therefore, the major aim of the current study is to employ a novel in silico method combined with experimental validation to explore off-targets and prioritize the enriched molecular pathways related to the specific cardiovascular events other than their intended targets by deriving relationship between drug-target-pathways and cardiovascular complications in order to help onco-cardiologists for the management of strategies to minimize cardiotoxicity. A systems biological understanding of the multi-target effects of a drug requires prior knowledge of proteome-wide binding profiles. In order to achieve the above, we have utilized PharmMapper, a web-based tool that uses a reverse pharmacophore mapping approach (spatial arrangement of features essential for a molecule to interact with a specific target receptor), along with KEGG for exploring the pathway relationship. In the validation part of the study, predicted protein targets and signalling pathways were strengthened with existing datasets of DrugBank and antibody arrays specific to vascular endothelial growth factor (VEGF) signalling in the case of 5-fluorouracil as direct experimental evidence. The current systems toxicological method illustrates the potential of the above big-data in supporting the knowledge of onco-cardiological indications which may lead to the generation of a decision making catalogue in future therapeutic prescription.

A novel liquid chromatography/tandem mass spectrometry (LC–MS/MS) based bioanalytical method for quantification of ethyl esters of Eicosapentaenoic acid (EPA) and Docosahexaenoic acid (DHA) and its application in pharmacokinetic study

&NA; Omega‐3 fatty acids are clinically useful and the two marine omega‐3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are prevalent in fish and fish oils. Omega‐3 fatty acid formulations should undergo a rigorous regulatory step in order to obtain United States Food and Drug Administration (USFDA) approval as prescription drug. In connection with that, despite quantifying EPA and DHA fatty acids, there is a need for quantifying the level of ethyl esters of them in biological samples. In this study, we make use of reverse phase high performance liquid chromatography coupled with mass spectrometry (RP‐HPLC–MS)technique for the method development. Here, we have developed a novel multiple reaction monitoring method along with optimized parameters for quantification of EPA and DHA as ethyl esters. Additionally, we attempted to validate the bio‐analytical method by conducting the sensitivity, selectivity, precision accuracy batch, carryover test and matrix stability experiments. Furthermore, we also implemented our validated method for evaluation of pharmacokinetics of omega fatty acid ethyl ester formulations. Graphical abstract Figure. No caption available. HighlightsAn RPLC–MS/MS based MRM method for EPA and DHA ester quantification.Does not required any prior derivatization/processing.Validated method for evaluation of pharmacokinetics of EPA/DHA esters.

Role of Antioxidants in Human Health

Association of diet with human health and disease has been known for centuries. Because of humans’ geographical origin, the diet and its compositional variability are high among populations. Human diet, including fruits, vegetables, nuts, and other animal sources has rich sources of bioactive molecules and antioxidants. Majority of human diet derived from plant sources, which contains polyphenols including flavonoids and phenolic acids, accounted for 90 %, and most of them possess antioxidant activity. Oxidative stress owing to excess of free radicals not neutralized by antioxidant defense enzymes leads to several degenerative diseases including cardiovascular diseases (CVDs), diabetes, kidney disease, cancer, neurological disorders, obesity, and aging. Hence, antioxidant dietary supplements are the attractive strategy to overcome these diseases. Therefore, in this chapter, we have focused on the overview of diet, antioxidants, and function of various plant antioxidant constituents. Furthermore, we have illustrated the role of oxidative stress on various diseases including CVD, cancer, and diabetes. Beneficial effects of various antioxidants and other antioxidant system stimulators on in vitro and in vivo models are explained. Along with this, we provide notable evidences from clinical trials using antioxidants on various diseases.